EPA Seeks Court‑Ordered Removal of 4 PFAS Limits
By Kevin Westerling,
@KevinOnWater
The U.S. EPA is testing a new procedural strategy to remove four PFAS drinking‑water limits from ongoing litigation, according to a recent report from Bloomberg Law. The agency is asking the D.C. Circuit Court of Appeals to invalidate those limits on the grounds that the EPA itself committed a procedural misstep when issuing the 2024 PFAS rule — an argument that, if accepted, could immediately wipe the limits from federal regulation without going through the usual public comment process.
A Novel Attempt To Accelerate Rollback
Specifically, the EPA asserts that it combined key rulemaking steps in a way that prevented required public comment and argues that this defect renders the standards for four Hazard Index (HI) PFAS compounds — PFBS, PFHxS, PFNA, and HFPO‑DA (GenX) — unlawful under the Safe Drinking Water Act (SDWA), which contemplates a sequential rulemaking process in which the agency issues a regulatory determination (with an opportunity for public comment) before proposing and finalizing a National Primary Drinking Water Regulation (NPDWR). [NOTE: PFHxS, PFNA, and HFPO‑DA each have standalone MCLs of 10 ppt, while PFBS does not have a standalone MCL and is regulated only as part of the HI mixture.]
If the court agrees that the EPA failed to provide the required opportunity for comment at the determination stage, the agency could nullify the HI limits immediately and — somewhat ironically — avoid the notice‑and‑comment process normally required to rescind drinking‑water protections.
This represents a dramatic shift from the agency’s earlier position defending the rule. As recently as late 2024, the EPA filed briefs asserting it had followed SDWA procedures correctly and that the PFAS limits were grounded in strong science. But in 2025, the agency pivoted — first announcing an administrative plan to revisit the four PFAS standards, then asking the court directly to throw them out. The new strategy is the latest iteration of that pivot.
Why The EPA’s Approach Matters
For the EPA, persuading the court to vacate the standards would provide two advantages:
- Speed: Rolling back the PFAS limits via litigation would be far faster than the EPA rewriting the rule from scratch, with extensive technical justification, comment periods, and potential court challenges.
- Reduced Public Blowback: Environmental groups contend that the EPA’s court‑centered approach is an attempt to subvert dissent. The Environmental Working Group, for example, warned to Chemical & Engineering News (C&EN) that the EPA is trying to “evade public accountability” by handing rollback authority to the court.
What Happens Next
The D.C. Circuit’s ruling on EPA’s request will determine whether the four PFAS limits stay in effect during the broader challenges to the 2024 rule. The court has already shown reluctance to dismantle the PFAS framework quickly — it previously denied the EPA’s separate attempt to vacate the same limits — but the EPA’s newly framed argument targets a different, more technical legal question.
If the EPA succeeds, utilities may see immediate regulatory relief on some PFAS obligations. If it fails, the four PFAS limits remain enforceable while litigation and the EPA’s administrative reconsideration continue in parallel.
Water Online will continue tracking this case as the court weighs whether procedural missteps — real or perceived — outweigh the SDWA’s mandate to safeguard public health.